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i- • Collecting soil samples every five feet. <br /> • Analyzing soil samples by EPA methods 5030, 8020 and the DHS extraction <br /> method for petroleum hydrocarbons. <br /> 3.2 Field Methods <br /> 3.2.1 Drilling of Soil Borings <br /> Prior to the commencement of drilling, Underground Services Alert was notified. When <br /> drilling commenced borings were advanced using a hollow stem auger operated by a <br /> California C-57 licensed driller. The IT field geologist conducted a tailgate safety meeting <br /> prior to drilling. <br /> All augers were thoroughly cleaned prior to drilling each borehole. The split spoon sampler <br /> -- and brass tube inserts were cleaned prior to each sampling event with a non-phosphate <br /> detergent scrubbing followed by a methanol rinse, and a final distilled water rinse. Boreholes <br /> were logged and soil samples will be obtained by using a modified California sampler undejL <br /> the direction of IT's field geologist. Soils were described using the visual method of the <br /> Unified Soil Classification System (USCS). Boring logs are contained in Appendix B. <br /> 3.2.2 Soil Sampling <br /> Sampling methods included grab samples for soil description and examination as well as <br /> samples in decontaminated brass tubes for laboratory analysis. Samples were taken of vadose <br /> zone soils every five feet (beginning at grade level) until the borings reached design depth. <br /> Groundwater was not encountered in any boring. <br /> Recovered samples and representative drill cuttings were screened for the release of volatile <br /> organic hydrocarbons with an organic vapor analyzer equipped with a photoionization <br /> detector. This instrument was calibrated by the field geologist prior to use. After the sampler <br /> was opened brass tube ends were immediately sealed with aluminum foil and fitted with end <br /> caps to prevent the loss of volatile compounds. Each tube was then placed in a separate <br /> ziploc bag and sealed with security tape. Samples were stored in a refrigerated ice chest and <br /> delivered to a DOHS certified laboratory for chemical analysis at the end of the work day. <br /> Chain-of-Custody and Request-for-Analysis forms accompanied the samples at all times <br /> (Appendix Q. <br /> MA/8-12-91/ENG/9284MER 3 <br />